Where a court overrules a long-standing common-law rule such as the public duty rule and establishes a new principle of law, this principle is presumed to be retroactive in application unless the court expressly states otherwise or such implementation would harm the rule’s applicability or raise clear equitable concerns.The 1st District Appellate Court affirmed in part and reversed in part a decision by Cook County Circuit Judge Sophia H. Hall.In 1976, Advocate Health and Hospitals Corp. submitted a plan to modify …